1. Field of the Invention
The present invention relates to aiming devices, and, more particularly, to aiming devices for medical implants.
2. Description of the Related Art
Aiming devices, such as jigs, are known in the art for aligning openings on orthopaedic implants with devices, such as bone screws, to affix bone fragments to the orthopaedic implants. The use of a jig allows for a user to insert the bone screws into a patient without the need for fully exposing the bone during surgery. The jig is typically connected to an end of the orthopaedic implant closest to an incision, with openings formed on the jig aligning with respective openings formed in the implant. To ensure proper alignment of the jig openings with the implant openings, an imaging technique such as fluoroscopy can be used to help adjust the jig until it is properly aligned. Once the jig is properly aligned, the bone screws can be passed through the jig openings and attached to their respective implant openings.
Most jigs in use today are designed to be used in conjunction with orthopaedic implants that have simple angle screw trajectories, i.e., the implant openings are not angled relative to both the x-axis and y-axis of the implant. Such trajectories are relatively simple to align with known jigs.
However, some orthopaedic implant devices incorporate compound angled screw trajectories, i.e., the implant openings are angled relative to both the x-axis and y-axis of the implant. Implants with compound angled screw trajectories have seen more widespread use due to evolving surgical techniques and the benefits that have been realized by using compound angled screw trajectories, such as compensation for various fracture patterns and good bone purchase. Such compound angled screw trajectory implants cannot be targeted with traditional jig devices for a variety of reasons, including difficulty of aligning the jig openings with the implant openings. While fluoroscopy alone has been used to target implants with compound angled screw trajectories, this targeting technique is not always feasible due to difficulty, time constraints, costs, and the risk of exposing the patient and surgical team to excessive radiation.
What is needed in the art is a more effective targeting device for targeting implants with compound screw trajectories.